Raspberry Pi boosts Pi 5 performance with SDRAM tuning

submited by

Style Pass

2024-12-02 17:30:03

tl;dr Raspberry Pi engineers tweaked SDRAM timings and other memory settings on the Pi, resulting in a 10-20% speed boost at the default 2.4 GHz clock. I of course had to test overclocking, which got me a 32% speedup at 3.2 GHz! Changes may roll out in a firmware update for all Pi 5 and Pi 4 users soon.

My quest for the world record Geekbench 6 score on a Pi 5 continues, as a couple months ago Martin Rowan used cooling and NUMA emulation tricks to beat my then-record score.

But Raspberry Pi's engineers are tweaking memory timings even further. They've talked to Micron and implemented a number of small tweaks that—along with NUMA emulation—really add up to a performance improvement for multi-core workloads. And even a little improvement for single-core!

The sdram refresh interval is currently using the default data sheet settings. You can actually monitor the temperature of the sdram and it reports if refresh at half or quarter the rate can be done. That allows the overhead due to refresh to be reduced by a half or a quarter which does improve benchmark results.